> ## Documentation Index
> Fetch the complete documentation index at: https://fastql.vachagan.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# GraphQL-over-HTTP contract

> Supported request formats, endpoint options, and adapter extension boundary.

The shared handler accepts GET query parameters and POST JSON bodies with
`query`, `variables`, `operationName`, and `extensions`. POST supports
`application/json` and `application/graphql-response+json`. Mutations and
subscriptions require POST.

Malformed transport input returns a structured `4xx` error. Once a GraphQL
request is decoded, parse, validation, and resolver failures use the normal
GraphQL `data` and `errors` result shape.

GraphiQL, SDL, and introspection JSON are independently configurable:

```python theme={null}
create_fastapi_router(
    schema,
    graphiql=True,
    schema_path="/schema.graphql",
    introspection_path="/schema.json",
)
```

Disable these options in production when schema discovery is not intended. CORS,
authentication, CSRF, rate limiting, and exception reporting belong to the host
framework.

## Extension boundary

A third-party adapter converts its native request into `HTTPRequest`, awaits
`GraphQLHTTPHandler.handle`, then converts `HTTPResponse` back into the native
response. The adapter must pass the native request, application, and request state
so FastQL can construct `HTTPContext` without importing that framework.

The initial contract excludes WebSocket subscriptions, multipart uploads,
batching, persisted queries, and incremental or streaming delivery.